Sanguin International Limited

RS232 Connections

RS232

A variety of Sanguin products use Serial ports for transfer of data via RS232, Below are generic connection diagrams for the cables, plugs and sockets Note that some instruments may have other requirements, please refer to the Instrument manufacturer's documentation.

RS232 Pin Assignments

25 pin plug/socket		9 pin plug/socket
Pin 1	Protective Ground (Gnd)	Pin 1	Line Detector (DCD)
Pin 2	Transmit Data (TX)	Pin 2	Received Data (RX)
Pin 3	Received Data (RX)	Pin 3	Transmit Data (TX)
Pin 4	Request To Send (RTS)	Pin 4	Data Terminal Ready (DTR)
Pin 5	Clear To Send (CTS)	Pin 5	Signal Ground (SG)
Pin 6	Data Set Ready (DSR)	Pin 6	Data Set Ready (DSR)
Pin 7	Signal Ground (SG)	Pin 7	Request To Send (RTS)
Pin 8	Line Detect (DCD)	Pin 8	Clear To Send (CTS)
Pin 20	Data Terminal Ready (DTR)	Pin 9	Ring Indicator (RI)
Pin 22	Ring Indicator (RI)

Simple 3 wire. This method uses no hardware (RTS/CTS) handshaking, instead, a connection between pins 7(RTS) & 8(CTS) provides the necessary signals that emulate hardware handshaking. Note that problems may occur in that the instrument may receive acknowledgements from a PC before it is ready to process them. In this case, a response delay may have to be incorporated.

7 wire. This method requires that hardware handshaking (RTS/CTS) is in effect, whilst potentially slower than the 3 wire method (above), this method may facilitate better data flow especially when connecting a PC to an older instrument.